//用两个栈实现一个队列。队列的声明如下，请实现它的两个函数 appendTail 和 deleteHead ，分别完成在队列尾部插入整数和在队列头部删除整数的
//功能。(若队列中没有元素，deleteHead 操作返回 -1 )
//
//
//
// 示例 1：
//
//
//输入：
//["CQueue","appendTail","deleteHead","deleteHead","deleteHead"]
//[[],[3],[],[],[]]
//输出：[null,null,3,-1,-1]
//
//
// 示例 2：
//
//
//输入：
//["CQueue","deleteHead","appendTail","appendTail","deleteHead","deleteHead"]
//[[],[],[5],[2],[],[]]
//输出：[null,-1,null,null,5,2]
//
//
// 提示：
//
//
// 1 <= values <= 10000
// 最多会对 appendTail、deleteHead 进行 10000 次调用
//
//
// Related Topics 栈 设计 队列 👍 744 👎 0


//leetcode submit region begin(Prohibit modification and deletion)
class CQueue {
    arr: any;
    constructor(arr = []) {
        this.arr = arr
    }

    appendTail(value: number): void {
        this.arr.push(value)
    }

    deleteHead(): number {
        if (this.arr.length) {
            const del = this.arr[0]
            this.arr = this.arr.slice(1)
            return del
        }
        else return -1
    }
}

/**
 * Your CQueue object will be instantiated and called as such:
 * var obj = new CQueue()
 * obj.appendTail(value)
 * var param_2 = obj.deleteHead()
 */
//leetcode submit region end(Prohibit modification and deletion)
